/*
 * Labjack Tools
 * Copyright (c) 2003-2007 Jim Paris <jim@jtan.com>
 *
 * This is free software; you can redistribute it and/or modify it and
 * it is provided under the terms of version 2 of the GNU General Public
 * License as published by the Free Software Foundation; see COPYING.
 */

#include <errno.h>
#include <stdint.h>
#include <stdlib.h>
#include <unistd.h>
#include <stdio.h>
#include <string.h>
#include <sys/types.h>
#include <math.h>

#include "netutil.h"
#include "compat.h"

#include "debug.h"
#include "nerdjack.h"
#include "util.h"
#include "netutil.h"
#include "ethstream.h"

#define NERDJACK_TIMEOUT 5	/* Timeout for connect/send/recv, in seconds */

//Struct holding information about how channels should be reordered for output
typedef struct
{
  int numCopies;
  int *destlist;
} deststruct;

typedef struct __attribute__ ((__packed__))
{
  unsigned char headerone;
  unsigned char headertwo;
  unsigned short packetNumber;
  unsigned long lwipmemoryused;
  unsigned short adcused;
  unsigned short packetsready;
  signed short data[NERDJACK_NUM_SAMPLES];
} dataPacket;

/* Choose the best ScanConfig and ScanInterval parameters for the
   desired scanrate.  Returns -1 if no valid config found */
int
nerdjack_choose_scan (double desired_rate, double *actual_rate,
		      unsigned long *period)
{
  //The ffffe is because of a silicon bug.  The last bit is unusable in all
  //devices so far.  It is worked around on the chip, but giving it exactly
  //0xfffff would cause the workaround code to roll over.
  *period = floor ((double) NERDJACK_CLOCK_RATE / desired_rate);
  if (*period > 0x0ffffe)
    {
      info ("Cannot sample that slowly\n");
      *actual_rate = (double) NERDJACK_CLOCK_RATE / (double) 0x0ffffe;
      *period = 0x0ffffe;
      //info("Sampling at slowest rate:%f\n",*actual_rate);

      return -1;
    }
  //Period holds the period register for the NerdJack, so it needs to be right
  *actual_rate = (double) NERDJACK_CLOCK_RATE / (double) *period;
  if (*actual_rate != desired_rate)
    {
      //info("Sampling at nearest rate:%f\n",*actual_rate);
      return -1;
    }
  return 0;
}

int
nerdjack_detect (char *ipAddress)
{
  int32_t sock, receivesock;
  struct sockaddr_in sa, receiveaddr, sFromAddr;
  int bytes_sent, buffer_length;
  char buffer[200];
  char incomingData[10];
  unsigned int lFromLen;

  sprintf (buffer, "TEST");
  buffer_length = strlen (buffer) + 1;

  net_init ();

  sock = socket (PF_INET, SOCK_DGRAM, IPPROTO_UDP);
  receivesock = socket (PF_INET, SOCK_DGRAM, IPPROTO_UDP);

  /* Set nonblocking */
  if (soblock (sock, 0) < 0)
    {
      verb ("can't set nonblocking\n");
      return -1;
    }

  /* Set nonblocking */
  if (soblock (receivesock, 0) < 0)
    {
      verb ("can't set nonblocking\n");
      return -1;
    }


  int opt = 1;
  setsockopt (sock, SOL_SOCKET, SO_BROADCAST, (void *) &opt, sizeof (int));

  if ((-1 == sock) || (-1 == receivesock))	/* if socket failed to initialize, exit */
    {
      verb ("Error Creating Socket\n");
      return -1;
    }

  //Setup family for both sockets
  sa.sin_family = PF_INET;
  receiveaddr.sin_family = PF_INET;

  //Setup ports to send on DATA and receive on RECEIVE
  receiveaddr.sin_port = htons (NERDJACK_UDP_RECEIVE_PORT);
  sa.sin_port = htons (NERDJACK_DATA_PORT);

  //Receive from any IP address, Will send to broadcast
  receiveaddr.sin_addr.s_addr = INADDR_ANY;
  sa.sin_addr.s_addr = INADDR_BROADCAST;

  bind (receivesock, (struct sockaddr *) &receiveaddr,
	sizeof (struct sockaddr_in));

  bytes_sent =
    sendto (sock, buffer, buffer_length, 0, (struct sockaddr *) &sa,
	    sizeof (struct sockaddr_in));
  if (bytes_sent < 0)
    {
      info ("Error sending packet: %s\n", strerror (errno));
      return -1;
    }

  lFromLen = sizeof (sFromAddr);

  if (0 >
      recvfrom_timeout (receivesock, incomingData, sizeof (incomingData), 0,
			(struct sockaddr *) &sFromAddr, &lFromLen,
			&(struct timeval)
			{
			.tv_sec = NERDJACK_TIMEOUT}))
    {

      return -1;
    }

  ipAddress = malloc (INET_ADDRSTRLEN);

  //It isn't ipv6 friendly, but inet_ntop isn't on Windows...
  strcpy (ipAddress, inet_ntoa (sFromAddr.sin_addr));

  close (sock);			/* close the socket */
  close (receivesock);
  return 0;
}

int
nerd_send_command (const char *address, void *command, int length)
{
  int ret, fd_command;
  char buf[3];
  fd_command = nerd_open (address, NERDJACK_COMMAND_PORT);
  if (fd_command < 0)
    {
      info ("Connect failed: %s:%d\n", address, NERDJACK_COMMAND_PORT);
      return -2;
    }

  /* Send request */
  ret = send_all_timeout (fd_command, command, length, 0, &(struct timeval)
			  {
			  .tv_sec = NERDJACK_TIMEOUT});
  if (ret < 0 || ret != length)
    {
      verb ("short send %d\n", (int) ret);
      return -1;
    }

  ret = recv_all_timeout (fd_command, buf, 3, 0, &(struct timeval)
			  {
			  .tv_sec = NERDJACK_TIMEOUT});

  nerd_close_conn (fd_command);

  if (ret < 0 || ret != 3)
    {
      verb ("Error receiving OK for command\n");
      return -1;
    }

  if (0 != strcmp ("OK", buf))
    {
      verb ("Did not receive OK.  Received %s\n", buf);
      return -3;
    }

  return 0;
}

//Initialize the channel structure to distill how data should be displayed
static void
nerd_init_channels (deststruct * destination, int numChannels,
		    int numChannelsSampled, int *channel_list)
{

  int channelprocessing = 0;
  int currentalign = 0;		//Index into sampled channels
  int i;
  int tempdestlist[NERDJACK_CHANNELS];

  //Clear out destination stuff
  for (i = 0; i < numChannelsSampled; i++)
    {
      destination[i].numCopies = 0;
    }


  for (channelprocessing = 0; channelprocessing < numChannelsSampled;
       channelprocessing++)
    {
      //Find out how many copies of each channel so we malloc the right things
      currentalign = 0;
      for (i = 0; i < numChannels; i++)
	{
	  if (channelprocessing == channel_list[i])
	    {
	      tempdestlist[currentalign] = i;
	      currentalign++;
	    }
	}



      //If this channel is wanted, set it up.
      if (currentalign > 0)
	{
	  destination[channelprocessing].numCopies = currentalign;
	  destination[channelprocessing].destlist =
	    malloc (destination[channelprocessing].numCopies * sizeof (int));
	  memcpy (destination[channelprocessing].destlist, tempdestlist,
		  destination[channelprocessing].numCopies * sizeof (int));
	}

    }

  return;

}

int
nerd_data_stream (int data_fd, int numChannels, int *channel_list,
		  int precision, int convert, int lines, int showmem,
		  unsigned short *currentcount, unsigned int period)
{
  //Variables that should persist across retries
  static dataPacket buf;
  static int linesleft = 0;
  static int linesdumped = 0;

  int index = 0;
  int charsprocessed = 0;
  int alignment = 0;
  signed short datapoint = 0;
  unsigned short dataline[NERDJACK_CHANNELS];
  long double voltline[NERDJACK_CHANNELS];
  int i;


  unsigned long memused = 0;
  unsigned short packetsready = 0;
  unsigned short adcused = 0;
  unsigned short tempshort = 0;
  int charsread = 0;

  int numgroups = 0;
  long double volts;

  unsigned int expectedtimeout =
    (period * NERDJACK_NUM_SAMPLES / NERDJACK_CLOCK_RATE) + 2;

  //Check to see if we're trying to resume
  //Don't blow away linesleft in that case
  if (lines != 0 && linesleft == 0)
    {
      linesleft = lines;
    }


  int numChannelsSampled = channel_list[0] + 1;

  //The number sampled will be the highest channel requested plus 1 (i.e. channel 0 requested means 1 sampled)
  for (i = 0; i < numChannels; i++)
    {
      if (channel_list[i] + 1 > numChannelsSampled)
	numChannelsSampled = channel_list[i] + 1;
    }

  deststruct destination[numChannelsSampled];

  nerd_init_channels (destination, numChannels, numChannelsSampled,
		      channel_list);


  //Now destination structure array is set as well as numDuplicates.

  //int numChannelsSampled = numChannels - numDuplicates;
  int numGroups = NERDJACK_NUM_SAMPLES / numChannelsSampled;


  //Loop forever to grab data
  while ((charsread =
	  recv_all_timeout (data_fd, &buf, NERDJACK_PACKET_SIZE, 0,
			    &(struct timeval)
			    {
			    .tv_sec = expectedtimeout})))
    {

      //We want a complete packet, so take the chars so far and keep waiting
      if (charsread != NERDJACK_PACKET_SIZE)
	{
	  //There was a problem getting data.  Probably a closed
	  //connection.
	  info ("Packet timed out or was too short\n");
	  return -2;
	}

      //First check the header info
      if (buf.headerone != 0xF0 || buf.headertwo != 0xAA)
	{
	  info ("No Header info\n");
	  return -1;
	}

      //Check counter info to make sure not out of order
      tempshort = ntohs (buf.packetNumber);
      //tempshort = (buf[2] << 8) | buf[3];
      if (tempshort != *currentcount)
	{
	  info ("Count wrong. Expected %hd but got %hd\n", *currentcount,
		tempshort);
	  return -1;
	}

      //Increment number of packets received
      *currentcount = *currentcount + 1;

      //Process the rest of the header and update the index value to be pointing after it
      charsprocessed = 12;
      memused = ntohl (buf.lwipmemoryused);
      adcused = ntohs (buf.adcused);
      packetsready = ntohs (buf.packetsready);
      alignment = 0;
      numgroups = 0;

      if (showmem)
	{
	  printf ("%lX %hd %hd\n", memused, adcused, packetsready);
	  continue;
	}

      index = 0;
      //While there is still more data in the packet, process it
      //use the destination structure to load the line before printing
      while (charsread > charsprocessed)
	{
	  datapoint = ntohs (buf.data[index]);
	  if (destination[alignment].numCopies != 0)
	    {
	      switch (convert)
		{
		case CONVERT_VOLTS:
		  if (alignment <= 5)
		    {
		      volts =
			(long double) (datapoint / 32767.0) *
			((precision & 0x01) ? 5.0 : 10.0);
		    }
		  else
		    {
		      volts =
			(long double) (datapoint / 32767.0) *
			((precision & 0x02) ? 5.0 : 10.0);
		    }
		  for (i = 0; i < destination[alignment].numCopies; i++)
		    {
		      voltline[destination[alignment].destlist[i]] = volts;
		    }
		  break;
		default:
		case CONVERT_HEX:
		case CONVERT_DEC:
		  for (i = 0; i < destination[alignment].numCopies; i++)
		    {
		      dataline[destination[alignment].destlist[i]] =
			(unsigned short) (datapoint - INT16_MIN);
		    }
		  break;
		}

	    }

	  //Each point is two bytes, so increment index and total bytes read
	  charsprocessed++;
	  charsprocessed++;
	  index++;
	  alignment++;

	  //Since channel data is packed, we need to know when to insert a newline
	  if (alignment == numChannelsSampled)
	    {
	      if (linesdumped != 0)
		{
		  switch (convert)
		    {
		    case CONVERT_VOLTS:
		      for (i = 0; i < numChannels; i++)
			{
			  if (printf ("%Lf ", voltline[i]) < 0)
			    goto bad;
			}
		      break;
		    case CONVERT_HEX:
		      for (i = 0; i < numChannels; i++)
			{
			  if (printf ("%04hX", dataline[i]) < 0)
			    goto bad;
			}
		      break;
		    default:
		    case CONVERT_DEC:
		      for (i = 0; i < numChannels; i++)
			{
			  if (printf ("%hu ", dataline[i]) < 0)
			    goto bad;
			}
		      break;
		    }
		  if (printf ("\n") < 0)
		    goto bad;
		}
	      else
		{
		  linesdumped = linesdumped + 1;
		  if (lines != 0)
		    {
		      linesleft++;
		    }
		}
	      alignment = 0;
	      numgroups++;
	      if (lines != 0)
		{
		  linesleft--;
		  if (linesleft == 0)
		    {
		      return 0;
		    }
		}
	      //If numgroups so far is equal to the numGroups in a packet, this packet is done
	      if (numgroups == numGroups)
		{
		  break;
		}
	    }
	}
      index = 0;
      charsprocessed = 0;
    }

  return 0;

bad:
  info ("Output error (disk full?)\n");
  return -1;

}

int
nerd_open (const char *address, int port)
{

  struct hostent *he;

  net_init ();

  int32_t i32SocketFD = socket (PF_INET, SOCK_STREAM, 0);

  if (-1 == i32SocketFD)
    {
      verb ("cannot create socket");
      return -1;
    }

  /* Set nonblocking */
  if (soblock (i32SocketFD, 0) < 0)
    {
      verb ("can't set nonblocking\n");
      return -1;
    }

  struct sockaddr_in stSockAddr;
  memset (&stSockAddr, 0, sizeof (stSockAddr));

  stSockAddr.sin_family = AF_INET;
  stSockAddr.sin_port = htons (port);

  he = gethostbyname (address);
  if (he == NULL)
    {
      verb ("gethostbyname(\"%s\") failed\n", address);
      return -1;
    }
  stSockAddr.sin_addr = *((struct in_addr *) he->h_addr);

  debug ("Resolved %s -> %s\n", address, inet_ntoa (stSockAddr.sin_addr));

  /* Connect */
  if (connect_timeout
      (i32SocketFD, (struct sockaddr *) &stSockAddr, sizeof (stSockAddr),
       &(struct timeval)
       {
       .tv_sec = NERDJACK_TIMEOUT}) < 0)
    {
      verb ("connection to %s:%d failed: %s\n",
	    inet_ntoa (stSockAddr.sin_addr), port, compat_strerror (errno));
      return -1;
    }

  return i32SocketFD;
}

//Generate an appropriate sample initiation command
int
nerd_generate_command (getPacket * command, int *channel_list,
		       int channel_count, int precision, unsigned long period)
{

  short channelbit = 0;
  int i;

  for (i = 0; i < channel_count; i++)
    {
      channelbit = channelbit | (0x1 << channel_list[i]);
    }

  //command->word = "GETD";
  command->word[0] = 'G';
  command->word[1] = 'E';
  command->word[2] = 'T';
  command->word[3] = 'D';
  command->channelbit = htons (channelbit);
  command->precision = precision;
  command->period = htonl (period);
  command->prescaler = 0;

  //sprintf(command,"GETD%3.3X%d%5.5d", channelbit,precision,period);

  return 0;

}

int
nerd_close_conn (int data_fd)
{
  shutdown (data_fd, 2);
  close (data_fd);
  return 0;
}